Is the Diet Approach Safe for You to Follow?
Make sure that the diet has been studied extensively for safety (this article provides information on whether that’s the case for the diet you’re considering) — and discuss any changes with your physician or registered dietitian before beginning a new diet. If you don’t have a dietitian, find one in your area at the Academy of Nutrition and Dietetics website. And do a self-check to ensure the diet fits with your values and preferences.

“Don't like eating meat?” asks Ginger Hultin, RDN, who’s in private practice in Seattle and a spokesperson for the Academy of Nutrition and Dietetics. “Then don't be paleo! Travel a lot and rely on eating out? The DASH diet may end in frustration for you.” The bottom line: The diet you choose needs to be safe and effective, while taking into account your lifestyle.

To lessen the confusion and get on the fast track to success, we got the skinny on some of the most popular diets out there today. So read on to see which plan might be best for you — and which diets to run away from at full speed!

Popular Diet Plans Backed by Some Scientific Evidence
Ketogenic Diet (Keto)
This high-fat, adequate-protein, low-carb fad diet sends the body into a state of ketosis, in which the body uses stored fat for energy instead of carbohydrates. Past research suggests the ketogenic, or “keto,” diet can be an effective weight loss method, but to be successful, you must follow the plan consistently with no cheat days — otherwise, you’re just eating a high-fat diet that may be high in unhealthy fats for no reason.

(A pro tip? If you're planning on doing the diet, check out a complete keto food list and read up on the healthiest fats for keto diet followers.)

Although the keto diet is popular among people with type 2 diabetes, you should avoid this diet if you have type 1 diabetes or other specific metabolic disorders.

No matter what your current state of health, you should speak with your physician before beginning the ketogenic diet, advises the Cleveland Clinic.

One of this diet's biggest hurdles? Saying goodbye to bread and other carbs. “It can be challenging to make sure to hit the low levels recommended for carbohydrates,” says Hultin. “This diet likely means a lot of planning ahead and bringing food with you to parties and events.”

You'll also want to be prepared for some of the plan's notable side effects, like keto-related diarrhea and constipation, fatigue, mood swings, headaches, and bad breath. These symptoms are a common part of the so-called keto flu, which happens as your body adjusts to burning fat rather than carbs for fuel, experts say.

Learn More About the Keto Diet

Paleo Diet
“A lot of people think the foundation of a paleo diet is high-fat meat, but I suggest that it’s vegetables,” says Hultin. The concept is to eat only foods — including meat, fish, poultry, eggs, fruits, and vegetables — that would have been available to our Paleolithic ancestors. This means grains, dairy, legumes, added sugar, and salt are all no-nos.

With this eating style, you’re looking at a lot of menu planning and preparation.

One systematic review and meta-analysis suggested the diet could lead to weight loss, but the Academy of Nutrition and Dietetics warns the plan could leave you low on carbs, plus it doesn’t allow for nutrient-dense foods like whole grains, legumes, and dairy. You’re also at risk of missing vitamins and minerals like calcium, vitamin D, and B vitamins, per the Harvard T.H. Chan School of Public Health.

This also means that not getting enough of bone-fortifying nutrients like calcium can put you at risk for osteoporosis, notes UC Davis Health.

Learn More About the Paleo Diet Here

Atkins Diet
This low-carb, high-protein diet has been around for decades. In fact, some say the keto diet is the new Atkins, though these popular low-carb plans are markedly different.

According to the Atkins website, the plan works in phases, with a very low daily net carb allowance of about 20, 40, or 100 grams (g) in the first phase, meaning the diet may send you into ketosis. How many net carbs you need to stay under depends on the plan you opt for. (You can calculate net carbs by subtracting fiber and sugar alcohols from total carbs. This value, though an unofficial nutritional term, can give you an estimate of how much a food might affect blood sugar levels.) Unlike the keto diet, you’re allowed more carbs as the phases continue.

In one past review, researchers found that the Atkins diet can yield modest long-term weight loss, similar to that of the WW eating plan.

Because the diet is low in carbs, it may not be appropriate for someone who is on insulin or has diabetes — and because it’s high in protein, you’d want to avoid it if you have kidney disease, according to Mayo Clinic.

Learn More About the Atkins Diet

DASH Diet
“This is a great way of eating that I highly recommend to many clients, and I even model in my own life,” says Elizabeth Shaw, RDN, who is in private practice in San Diego and is the coauthor of Fertility Foods Cookbook. “Since the premise of the diet is designed to help people who have high blood pressure, low-sodium foods are recommended. But considering that most Americans exceed their daily sodium levels anyway, it’s not surprising that dietitians recommend this style of eating for treating many different conditions, such as heart disease and obesity.”

The DASH diet, or Dietary Approaches to Stop Hypertension, is mainly focused on reducing sodium intake and increasing consumption of fruits and vegetables, according to Mayo Clinic.

In one meta-analysis, people with or without hypertension who followed the DASH diet saw an improvement in blood pressure compared with a control group who did not follow the DASH diet.

U.S. News & World Report has also consistently listed the DASH diet as a top diet in its annual rankings.

Learn More About the DASH Diet

MIND Diet
The MIND diet, or Mediterranean-DASH Intervention for Neurodegenerative Delay, is a sort of hybrid between the DASH diet and the Mediterranean diet. It features foods meant to slow the progression or development of Alzheimer’s disease, the most common form of dementia and an incurable neurodegenerative condition that more than six million Americans are living with, according to the Alzheimer’s Association. Some research backs up this notion, including one study that found a link between following the MIND diet and a reduced risk of dementia, though more research is needed.

Emphasizing vegetables, berries, beans, whole grains, olive oil, fish, and wine, according to Mayo Clinic, it also calls for a reduction in saturated fat and trans fat, as Harvard Health Publishing notes.

Because the MIND diet focuses on cutting unhealthy fats and emphasizes eating whole, fresh foods, people who follow this eating pattern may lose weight while doing so.

Learn More About the MIND Diet